The Cubs' next big thing will head to Triple-A Iowa to continue to work on his defense behind the plate, but he used the six-game stint to prove he will be back in the majors...at some point.

"I loved the fact that he just competes," Cubs manager Joe Maddon said after Sunday's 8-0 win over the Twins. "He had a couple tough at-bats, but he competed the entire game. And that's what you notice.

"As it moves down the road when he gets back up here, the fact that he's a competitor, that matters. A lot, actually. So I was really pleased with that."

Schwarber finished the week with a .364 average, .982 OPS and 6 RBI on a homer and a triple, drawing a high compliment from Maddon, who said the rookie handled everything "perfectly."

After striking out in his debut Tuesday, Schwarber announced his arrival by going 4-for-5 in Cleveland Wednesday, helping to lead the charge in the Cubs' 17-0 slaughter over the Indians.

But he finished just 2-for-12 over his last three games, including that two-run single. He struck out six times during the three games in Minnesota, too often expanding the zone and helping Twins pitchers get him out.

"The stuff [from MLB pitchers] is really good," Schwarber said. "That's when your approach has to come in. You can't be chasing pitches. I got myself into the trouble the last couple days by chasing some pitches out of the zone.

"It's time to get back to being patient and swinging at pitches in the zone. That's when I'm going to have success - swinging at strikes, not balls."

On one occassion Saturday, Schwarber expanded the zone again, striking out with only one out and a runner on third when the Cubs could have used a run in the sixth inning of a tie game.

The Cubs were actually glad Schwarber experienced some adversity in the big leagues, since he hasn't endured much in the way of struggles in the minors (.333 average, 31 homers, 92 RBI, 1.042 OPS in 130 games since being selected No. 4 overall in the 2014 Draft.)

"I love the fact that he had some success and maybe struggled just a little bit so he can understand it's not that easy to do all this," Maddon said. "He's gonna know he has to make adjustments. He's gonna know the way this league works, how teams will scout and analyze him until they find that little thing and then you have to guard against it and make an adjustment.

"Primarily, he was just swinging at the ball up and he knows that and [the Twins knew] that. So he's just got to stop doing that. They're balls. And he'll be fine."

The Cubs want Schwarber to go back down to the minors and work on his defense as a catcher, learning how to frame pitches, call a game and everything else that comes with the most demanding position on the field.

Barring a drastic rule change in Major League Baseball, the Cubs won't have the benefit of the designated hitter for more than a few games a season, so if he's going to be a big part of the future, Schwarber has to be more than just a guy who can hit.

But he knows that.

"[Hitting] was fun, but before games, I was always trying to get better defensively, because obviously I have to play a position," Schwarber said. "I had to take advantage of my time beforehand or in games, whether it's good at-bats and always trying to learn even when you're not hitting, thinking along with the catcher."

Schwarber only caught one inning during his brief trip up with the Cubs, coming in to receive the ninth inning of Tuesday's game.

But he spent the week sitting alongside the Cubs veteran catching duo - Miguel Montero and David Ross - as well as catching instructor Mike Borzello before and during games, trying to soak up anything he could.

The Cubs let Schwarber catch veteran starter Jason Hammel's side session in Minnesota and the 22-year-old also hopped out to warm up Jon Lester and Jake Arrieta in between innings while Ross and Montero put their gear on.

"It was nice," Schwarber said of learning from Montero and Ross. "Being able to sit by them, talk to them during a game while one's catching and one's on the bench and sitting next to Borzello, thinking along with the game.

"It's great. Shows how much attention to detail they put into the game-calling. It is kind of an art. It's really cool to see how they do it."

Schwarber stood at his locker Sunday evening, insisting he wasn't disappointed by his assignment back to the minor leagues.

The Cubs had made it very clear from the start: This was only six games and that's it. Not even a full week of MLB time. No matter what the kid did - good or bad - he wasn't going to stay in the big leagues. Not as a catcher, outfielder or left-handed bat off the bench.

"We talked before [Sunday's] game about what was going to happen next," Maddon said. "Of course, he got it. I think we set it up properly before he came here. There was no gray area. He knew, regardless of how well he did, he was going back.

"And as you can see, there are different things to work on next. He definitely contributed, helped us win a couple games. He did an outstanding job. Him and [Borzello] got a chance to work defensively and we talked about all that stuff.

"It really doesn't happen often that a guy like that, a player like that, gets this opportunity for a finite moment, knows exactly what's going on, the fit is perfect and then goes back down with some specifics to work on. It really couldn't have turned out better."

Schwarber still has to answer the long-term questions about his ultimate position (catcher? left field? somewhere else?), but he's still determined to make it as a backstop.

And despite his advanced approach at the plate and early success, Schwarber knows he still has plenty to learn on the hitting side of things.

"It was a great experience," Schwarber said. "I can't thank these guys enough for being accepting, letting me come up and play with 'em. I'm glad I got to help the team win a couple games.

"It was a great experience and now it's time to go down and start working on all the things I need to work on and hopefully get back up here."

“I think it’s a terrible idea. I think it’s all terrible,” Jon Lester said last week at spring training, before the specifics of the new rules were even announced. “The beautiful thing about our sport is there’s no time.”

Big surprise coming from the Cubs’ resident old-schooler.

The new rules limit teams to six mound visits per every nine-inning game, with exceptions for pitching changes, between batters, injuries and after the announcement of a pinch hitter. Teams get an extra mound visit for every extra inning in extra-inning games. Also, commercial breaks between innings have been cut by 20 seconds.

That’s it. But it’s caused a bit of an uproar.

Contreras made headlines Tuesday when he told reporters that he’ll willingly break those rules if he needs to in order to put his team in a better position to win.

“I’ve been reading a lot about this rule, and I don’t really care. If I have to pay the price for my team, I will,” Contreras said. “There’s six mound visits, but what if you have a tight game? … You have to go out there. They cannot say anything about that. It’s my team, and we just care about winning. And if they’re going to fine me about the No. 7 mound visit, I’ll pay the price.”

Talking about pace-of-play rule changes last week, Cubs manager Joe Maddon said his team would adapt to any new rules. In Chicago baseball’s other Arizona camp, a similar tune of adaptation was being sung.

“Obviously as players we’ve got to make adjustments to whatever rules they want to implement,” White Sox pitcher James Shields said. “This is a game of adjustments, we’re going to have to make adjustments as we go. We’re going to have to figure out logistics of the thing, and I would imagine in spring training we’re going to be talking about it more and more as we go so we don’t mess it up.”

There was general consensus that mound visits are a valuable thing. So what happens if a pitcher and catcher need to communicate but are forced to do it from 60 feet, six inches away?

“Sign language,” White Sox catching prospect Zack Collins joked. “I guess you have to just get on the same page in the dugout and hope that nothing goes wrong if you’re out of visits.”

In the end, here’s the question that needs answering: Are baseball games really too long?

On one hand, as Lester argued, you know what you’re signing up for when you watch a baseball game, be it in the stands at a ballpark or on TV. No one should be shocked when a game rolls on for more than three hours.

But shock and fans' levels of commitment or just pure apathy are two different things. And sometimes it’s a tough ask for fans to dedicate four hours of their day 162 times a year. So there’s a very good reason baseball is trying to make the game go faster, to keep people from leaving the stands or flipping the TV to another channel.

Unsurprisingly, Lester would rather keep things the way they are.

“To be honest with you, the fans know what they’re getting themselves into when they go to a game,” Lester said. “It’s going to be a three-hour game. You may have a game that’s two hours, two hours and 15 minutes. Great, awesome. You may have a game that’s four hours. That’s the beautiful part of it.

“I get the mound visit thing. But what people that aren’t in the game don’t understand is that there’s so much technology in the game, there’s so many cameras on the field, that every stadium now has a camera on the catcher’s crotch. So they know signs before you even get there. Now we’ve got Apple Watches, now we’ve got people being accused of sitting in a tunnel (stealing signs). So there’s reasons behind the mound visit. He’s not just coming out there asking what time I’m going to dinner or, ‘Hey, how you feeling?’ There’s reasons behind everything, and I think if you take those away, it takes away the beauty of the baseball game.

“Every game has a flow, and I feel like that’s what makes it special. If you want to go to a timed event, go to a timed event. I’m sorry I’m old-school about it, but baseball’s been played the same way for a long time. And now we’re trying to add time to it. We’re missing something somewhere.”

Whether limiting the number of mound visits creates a significant dent in this problem remains to be seen. But excuse the players if they’re skeptical.

“We’ve got instant replay, we’ve got all kinds of different stuff going on. I don’t think (limiting) the mound visits are going to be the key factor to speeding this game up,” Shields said. “Some pitchers take too long, and some hitters take too long. It’s combination of a bunch of stuff.

“I know they’re trying to speed the game up a little bit. I think overall, the game’s going as fast as it possibly could. You’ve got commercials and things like that. TV has a lot to do with it. There’s a bunch of different combinations of things. But as a player, we’ve got to make an adjustment.”